After last week’s outlier – an occupational hazard in polling – it is back into the territory of wafer-thin leads in this week’s Ashcroft National Poll. The Conservatives are ahead by a single point with 29 per cent; Labour are unchanged on 28 per cent, UKIP down one at 15 per cent, the Liberal Democrats up one at 9 per cent, the Greens up three at 11 per cent and the SNP up a point at 5 per cent.

The ANP has tended to find a lower combined share for the two main parties than most other surveys, and this is the lowest two-party share I have yet recorded. It is also the first time both Labour and the Tories have scored less than 30 per cent. One factor could be that the Greens have benefited from their prominence in the arguments over TV debates – in which case it will be interesting to see in the coming weeks whether they can sustain their share.

Asked who they most trust to manage the economy in the best interests of Britain, people chose Cameron and Osborne over Miliband and Balls by a 15-point margin – down four points since October, but with the Labour team still stuck on 26 per cent (and only 22 per cent among swing voters). While men preferred the Tory pair by 20 points, women favoured them by only a nine-point margin. Nearly three in ten Labour voters said either that they most trusted Cameron and Osborne (16 per cent) or that they trusted neither or didn’t know (13 per cent).

For all the activity since the beginning of January, half the electorate said they were so far paying little (27 per cent) or no attention (22 per cent) to the parties’ campaigns. Men were more likely to say (or claim) that they were following events than women, and only 13 per cent in total said they were paying a great deal of attention, which probably includes a fair number giving themselves the benefit of the doubt. Swing voters (56 per cent) were more likely than the country as a whole to admit to paying little or no attention to what the parties were saying.

This answer rings true from my latest focus groups, held last week with undecided voters in Croydon and Dudley. Such groups will be a regular feature of my research from now until the election, helping to illuminate the numbers and to explain why people think what they think, as well as how many people think what.

Focus groups can be a useful reality check to those involved in politics, and this batch were no exception. After all the frantic launching and speechmaking of the last fortnight, did the election feel imminent? “I don’t think there’s been much in the media”, observed a lady in a moment that would leave overworked party press officers with their heads in their hands. Others agreed: “There’s no excitement building. It feels more like a local election. There’s something coming but not anything big like who’s going to run the country.”

One political story that most had spotted (but by no means all – “it’s not the sort of thing that’s on the local radio news”) was the TV debate controversy. As Ed Miliband foresaw at last week’s PMQs, “nobody but nobody” believed Cameron’s objections to the proposed format were founded on a wish to be fair to the Greens: clearly he was “more worried about Farage” and wants someone “to take the heat off himself”. Neither were they convinced that the Greens should be invited – they are, as one lady put it, “a bit more niche than UKIP”.

But if Cameron’s objections were transparently “a tactic”, there was no outrage at his reluctance to take part, though all thought an empty Prime Ministerial chair amid the other leaders would look very bad indeed. Most said they would watch the debates if they were on (or at least the highlights – “I don’t want to listen to an hour and a half of it”), but there was no indignation at the potential denial of anything they regarded as a democratic right. Number Ten is probably right to calculate that the PM has more to lose by taking part in debates than by being seen as the reason for their not happening at all.

None of our participants had seen the rival posters launched by Labour and the Conservatives last week. What did they make of the Labour claim that “the Tories want to cut spending on public services back to the levels of the 1930s, when there was no NHS”?

“That seems very unlikely,” frowned one fair-minded soul. “That’s a lie. Nonsense. It’s completely misleading,” declared another. “That sort of thing annoys me,” added another, and all agreed that “anything like that you take with a pinch of salt”.

The trouble is, “there are cuts behind the scenes and there is sneaking privatisation”. Therefore “there is a grain of truth, or more than a grain” in Labour’s claim, extreme exaggeration though it is.

The Conservative poster urging voters to “stay on the road to a stronger economy” was better received. People thought the message was positive, powerful and largely believable, although they questioned some of the specifics. There was also a lesson in the ambiguities of the verbless political sentence. “1.75 million more people in work. 760,000 more businesses. The deficit halved”, proclaims the poster. “Are they predictions?” someone asked.

Most realised they were things the government had achieved, or at least claims to have done. Again, though, the figures could not be taken at face value: “They will be at the minimum wage, most of those jobs, or zero hour contracts.” Still, the message of the poster chimed with most people’s view that the economy was improving overall – if not yet for them personally – and was at any rate “better than a cheap snipe”.

Over the next four months people will be bombarded with facts and statistics, not least from the parties. How will people make sense of them? Any such “fact” that comes from a party will be immediately discounted as being misleading or incomplete, even if it may contain a kernel of truth. Analysis from the BBC could not be regarded as gospel, since reporters could have biases of their own and even they had to get their figures from somewhere. Official statistics from sources like the Office for Budget Responsibility were only so much help, since different parties and commentators would interpret them in different ways. Even think tanks like the Institute for Fiscal Studies could not be taken entirely at face value: “are they totally independent? You don’t always know if the government is behind them or where they get their funding.” When it comes down to it, “you just have to read as much as possible and come to your own view”.

How were the party leaders coming across at this stage of the game? As always, people observed that Nigel Farage was a bit different from other leaders and less stuffy, but there was more than a note of scepticism – particularly in Croydon, and particularly among participants from ethnic minorities. “You get where he’s coming from, but it’s the way he says it – like the Romanians moving in next door and people not speaking English on the train.” He also has the luxury that “when you’re not going to win you can say whatever you like, like Clegg used to”.

A number of people noted that they had only heard UKIP talk about Europe and (especially) immigration – a complaint that had not surfaced for some time in my research but which may be more of a problem for the party as the election approaches. For that reason, some were keen to hear what he would have to say in the TV debates, should they happen – a platform that could give him the chance to defy expectations by broadening some people’s view of UKIP, which confirms the wisdom of Downing Street’s reluctance to take part.

As is often the case, comments about Nick Clegg were not so much critical as sympathetic, which does not augur well for May (“he’s trying his best… he was always on a hiding to nothing”).

In the wake of the Paris attacks, people’s remarks about David Cameron often focused on the need for strong leadership in an uncertain world – a role that, from the candidates on offer, they could only imagine him fulfilling: “you need someone in authority who looks like they can cope with it”.

Perhaps the most notable feature of these groups of undecided voters was the absence of any enthusiasm for Labour – even among those who had voted for the party in 2010 – or any urgent desire for change. Nobody could recall any Labour promises, and the most positive thing anyone said about Ed Miliband was that “he talks sense on things like not privatising the NHS, but he’s not really on the ball, not in David Cameron’s league”. People could not say where he wanted to take Britain: “he hasn’t really made up his mind where he’s going… it’s as though he just wants to be a politician, and he’s faffing around to find some principles” – and, ominously, “it feels like he’s the interim Labour leader until the next one”.

If each leader were an animal, what would they be? Cameron would be a fox, being smart and sleek – or, less charitably, “a giraffe, looking down on everybody”. Farage? A peacock, or a weasel. Clegg? “A Chihuahua in David Cameron’s handbag”. Miliband? Puzzlement. “Certainly not a predator… one of those animals that, when you go to the zoo, you’re not bothered whether you see it or not.”

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